Of course you're not crazy - that's perfectly reasonable.
(then again, it's a bit like an alcoholic asking his friends at the pub whether he's drinking too much)
The most I've ever done in 80h was CPT-JNB-ADD-LHR-FRA-YYZ-YVR-SYD which actually was quite relaxing and enjoyable (two tickets; booking two trips back-to-back just happened to make sense).